A mobile device such as a smartphone, tablet, or electronic reader may include an ambient light sensor for detecting ambient light incident on a display of the device. The ambient light sensor may be provided at a periphery of the device, for example. An amount of light transmitted through, emitted by, or reflected by the display may be adjusted based on output from the sensor by controlling a backlight or frontlight unit of the display and/or driving circuitry for driving pixels of the display. For example, in bright ambient light conditions, the brightness of the display may be reduced to compensate for ambient brightness.
There has been an increasing trend towards reducing border areas of mobile devices in order to maximize the display area. A consequence of this trend has been a reduced amount of device real estate available for providing an ambient light sensor, an image sensor, or the like.